SPC AC 201628
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1128 AM CDT TUE JUL 20 2004
   
   VALID 201630Z - 211200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 45 NNW
   ELO 50 SSE DLH 25 ESE OSH 30 WNW BEH 40 NW DNV 20 NW CMI 35 E UIN 25
   NW IRK 30 S OMA GRI 40 ENE ANW 20 NNW HON 35 WNW JMS 75 NE MOT.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 SSE PFN 25 SSE MAI
   15 SSW AYS 40 W SAV 45 W AGS 10 SSW AVL CLT 30 NNW GSO 20 NNE PSK 35
   NE 5I3 15 NNE LEX 25 S CKV 30 SE PGO 15 ESE MLC 40 SSW OJC 20 NNE
   EMP 25 SW MHK 40 W END 55 ENE BGS 20 SE P07 ...CONT... 70 SSW GBN
   GBN 50 SW PRC 45 NNE IGM 65 WNW P38 10 NW TPH 40 SW U31 10 NNE BAM
   95 NNW WMC 30 ENE BNO 20 WNW BKE 35 SE ALW 20 E LWS 25 WSW S06 50 NW
   3TH 35 S 4OM 70 WNW 4OM.
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ERN DAKS ACROSS THE
   CORN BELT/MN INTO THE UPPER MS VLY...
   
   ...ERN DAKS/MID-MO VLY EWD INTO THE UPPER MS VLY...
   MESOSCALE FEATURES REMAIN RATHER WEAK LATE THIS MORNING. DOUBLE
   STRUCTURED WARM FRONTS APPEAR TO BE LOCATED FROM CNTRL IA NWWD ALONG
   THE MO RVR VLY AND ALSO FROM CNTRL WI NWWD INTO SERN MANITOBA. KEY
   FOCUS IS LIKELY TO BE ASSOCIATED WITH THE SRN-MOST BOUNDARY THIS
   AFTERNOON AND EVENING...PARTICULARLY OVER THE MID-MO RVR VLY.
   
   VAPOR IMAGERY SHOWS DUAL VORT MAXIMA MOVING EWD ACROSS THE CNTRL
   DAKS.  NRN IMPULSE SHOULD TRANSLATE ACROSS THE RED RVR VLY INTO
   NRN/CNTRL MN DURING PEAK HEATING.  AIR MASS DOWNSTREAM IS EXPECTED
   TO DESTABILIZE...THOUGH PATCHES OF MID-LAYER CLOUD MAY INHIBIT
   STRONG DESTABILIZATION.  NONETHELESS...TSTMS ARE APT TO DEVELOP
   VCNTY THE WARM FRONT AND MOVE ACROSS CNTRL/NRN MN THROUGH EVENING. 
   VERTICAL SHEAR WILL ALSO REMAIN MARGINAL TO SUPPORT SUPERCELLS.  A
   FEW STRONGER TSTMS MAY PRODUCE HAIL OR DAMAGING WIND GUSTS...BUT THE
   SLIGHT RISK ACROSS NRN/CNTRL MN INTO NRN WI WILL REMAIN CONDITIONAL.
    HIGHER THAN ANTICIPATED INSTABILITY VALUES COULD CONTRIBUTE TO MORE
   OF A SEVERE THREAT.
   
   HIGHER-END SEVERE WEATHER THREAT WILL EXIST FARTHER SOUTH AND WEST.
   STRONGEST HEATING/LOW-LEVEL LAPSE RATES WILL MAKE FOR A VERY
   UNSTABLE AIR MASS IN NERN NEB...NWRN IA...ERN SD AND SWRN MN.  NEAR
   70 DEGREES F SURFACE DEW POINTS BENEATH VERY STEEP MIDLEVEL LAPSE
   RATES WILL CONTRIBUTE TO MLCAPES OF 3000-3500 J/KG.  AS TAIL END OF
   THE SRN-MOST VORT MAX MOVES INTO THE REGION...CAP SHOULD ERODE AND
   TSTMS SHOULD INITIATE BY LATE AFTERNOON.  THOUGH THE FLOW THROUGH
   THE COLUMN WILL REMAIN WEAK...STRONG DIRECTIONAL SHEAR WILL REMAIN
   FAVORABLE FOR SUPERCELLS...SOME WITH VERY LARGE HAIL UP TO BASEBALL
   SIZE AND SEVERE WIND GUSTS.  THERE WILL ALSO BE A RISK OF AN ISOLD
   TORNADO...PARTICULARLY VCNTY SURFACE LOW/ WARM FRONT ACROSS NERN
   NEB...SERN SD...SWRN MN AND NWRN IA.  HOWEVER...LCLS WILL BE
   HIGH...ON THE ORDER OF 6000 FEET AGL.  UPSCALE GROWTH INTO A MCS MAY
   OCCUR OVERNIGHT ACROSS NRN/CNTRL IA OR SRN MN AS SWLY LLJ INCREASES.
    THIS MAY CARRY DAMAGING WIND/HAIL THREATS INTO THE UPPER MS VLY
   VERY LATE TONIGHT.
   
   LASTLY...A FEW TSTMS MAY DEVELOP ALONG THE WARM FRONT SEWD ACROSS
   SERN WI/NERN IL INTO THE UPPER MIDWEST VERY LATE THIS AFTERNOON OR
   EARLY EVENING. MIDLEVEL LAPSE RATES WILL NOT BE PARTICULARLY HIGH
   THIS FAR EAST...BUT DIRECTIONAL SHEAR AND MLCAPES OF 2500-3000 J/KG
   MAY CONTRIBUTE TO A COUPLE OF SUPERCELLS WITH HAIL/HIGH WINDS.
   
   ...NRN HIGH PLAINS...
   DESPITE STRONGER UPPER LEVEL SHORTWAVE TROUGH TRANSLATING ACROSS THE
   NRN ROCKIES ONTO THE PLAINS...INCREASINGLY DRY/DOWNSLOPE FLOW WILL
   BEGIN TO SCOUR OUT MOISTURE ACROSS THE NRN HIGH PLAINS THIS
   AFTERNOON.  CBS WILL DEVELOP ALONG THE HIGHER TERRAIN IN MT...BUT
   SHOULD WEAKEN AS THEY ENTRAIN THE DRIER AIR.
   
   ...NRN GREAT BASIN...
   AS MIDLEVEL TROUGH BEGINS TO MOVE EWD TODAY...TSTMS ARE EXPECTED TO
   DEVELOP OVER THE NRN GREAT BASIN.  PRESENCE OF MIDLEVEL THERMAL
   TROUGH AND 30-35 KTS OF VERTICAL SHEAR COULD CONTRIBUTE TO A FEW
   TSTMS TO BECOME ORGANIZED WITH SEVERE WIND GUSTS OR HAIL.
   
   ..RACY/JEWELL.. 07/20/2004
   
   ...NOTICE...
   FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
   LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
   GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
   HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
   INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.
   
   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED FOR 2000Z